Download - Salt Marsh Restoration
EMILY WALLISBIOSC 413
SPRING 2011
Salt Marsh Restoration
Basic Salt Marsh Ecology
Salt marshes occur in intertidal zones of moderate to low energy shorelines
Vegetation consists of various halophytic (salt tolerant) grasses, sedges, and rushes that are periodically flooded by estuarine waters
Basic Salt Marsh Ecology
Ecological values: Primary production Nutrient cycling Habitat for fish, birds, and other wildlife Stabilize shorelines High macroinvertebrate diversity
Threats to Salt Marshes
DredgingWaste dischargeHazardous spillsIndirect effects of other activities, such as
damming and agriculture Salinity changes Altered sedimentation rates Nutrient pulses
Natural threats to salt marshes include hurricanes and changes in sea level
Restoration Challenges
Salt marsh habitats are inherently variable in salinity, oxygenation, and velocity of incoming water due to slope
Marshes occur on a wide variety of substrates
Uncertainty of storm free periods that would be conducive to initiating a project
Restoration Challenges
MosquitoesInvasive species, such
as PhragmitesMinimizing human
interference
Salt Marsh Restoration Strategies
Topographical studies Slope of marsh must
ensure adequate influx and efflux of salt water
Reestablishing hydrology Modification of water
control structures to reestablish historical tidal rushing regimes
Salt Marsh Restoration Strategies
Controlling invasive species Phragmites can be
drastically reduced by controlling tidal hydrology
If hydrological manipulation is not feasible or necessary, Phragmites can be controlled with herbicide, burning, or manual removal. These processes usually take several years
Salt Marsh Restoration Strategies
Planting native halophytic vegetation Spartina- cordgrass Salicornia- glassworts Juncus- rushes Cyperus- sedges
Open-water marsh management (OWMM) Using tidal fishes to
control mosquito populations
Why restore salt marshes?
Important areas for faunal biodiversity including fishes, macroinvertebrates, and birds
Salt marshes serve as natural transition zones for oceanic energy, allowing a reduction in water velocity before it reaches land Flood protection
Why restore salt marshes?
Aesthetic appealGlobal averages
estimate a 30% loss in salt marsh habitat (Bostrom et al. 2011)
Crissy Marsh. San Francisco, CA
Works Cited
Athearn ND, Takekawa JY, Shinn JM. “Avian response to early tidal salt marsh restoration at former commercial salt evaporation ponds in San Francisco Bay, California, USA.” Natural Resources and Environmental Issues 15.1 (2009): 77-86. Web. 10 April 2011.
Bostrom C, Pittman S, Simenstad C, Kneib RT. “Seascape ecology of coastal biogenic habitats: advances, gaps, and challenges.” Marine Ecology Progress Series 427 (2011): 191-217. Web. 13 April 2011.
Broome SW, Seneca, ED, Woodhouse WW. “Tidal salt marsh restoration.” Aquatic Botany 32 (1998): 1-22. Web. 10 April 2011.
Johnston RJ, Magnusson G, Mazzotta MJ, Opaluch JJ. “Combining economic and ecological indicators to prioritize salt marsh restoration actions.” American Journal of Agricultural Economics 84:5 (2002): 1362-1370. Web. 10 April 2011.
Rhode Island Habitat Restoration. “Restoration Strategy”. Web. Wolters M, Garbutt A, Bekker RM, Bakker JP, Care PD. “Restoration of salt
marsh vegetation in relation to site suitability, species pool, and dispersal traits.” Journal of Applied Ecology 45 (2008): 904-912. Web. 10 April 2011.